TP-6200 10/12208 Appendix
Appendix D Alternator Protection
The 550 controller has built-in thermal protection forthe
alternator. This feature functions similarly to a thermal
circuit breaker. When the output current exceeds the
nominal rating for a short period of time the condition
causesthe fault shutdown. The amount of time at which
current is over the rating is inversely related to the
amount of current above the nominal rating. In other
words,the higher the current, the shorter the acceptable
time.
The current and time limits are defined by actual test
data and are maintained in the personality parameter
file. Although the equation for detecting a fault is
proprietary, some of the important limits are shown
below for informational purposes.
Rated Current Time Delay
200% 40 seconds
300% 10 seconds
425% 5 seconds
950% 1 second